Question

A wire in the form of a square with side $22cm$. It is reshaped and bent into the form of a circle. Calculate the area of this circle. ($\pi =\frac{22}{7}$)

Answer 1

Given that side of the square is $22$ $cm$

Perimeter of the square $=4a$

$=4\times 22cm$

$=88cm$

As the same wire is used to form a circle then both will have same perimeter.

Perimeter of circle $=$ Perimeter of square

$\Rightarrow 2\pi r=88$

$\Rightarrow 2\times \frac{22}{7}r=88$

$\Rightarrow r=\frac{88\times 7}{22\times 2}$

$\Rightarrow r=14cm$

Hence radius of the circle is $14cm$.

then,

Area of the circle $=\pi r^2$

$=\frac{22}{7}\times 14\times 14c{m}^2$

$=616c{m}^2$